The present invention relates to an integrated wiring system, and more particularly to an integrated wiring system suitable for controlling devices provided in an automobile.
In an automobile, it is necessary to perform various kinds of control, such as high-speed control (1 ms to 10 ms) and low-speed control (10 ms to 100 ms). Typical examples of systems which require high-speed control and processing of a large amount of information are ignition timing and fuel injection for an internal combustion engine. A typical example of low-speed control is control for electrical parts (such as a head lamp, a seat motor and a power window), which merely requires processing of a small amount of information.
Japanese Patent Laid-Open No. 230345/1984 discloses an integrated wiring system for controlling radio devices by performing serial multiplex data transmission of control signals over one or several signal transmission lines which are substituted for a multiplicity of control signal wires. However, in such arrangement, if various kinds of control are to be handled by a single communication protocol, a high-speed communication protocol must be employed, and it is thus necessary to apply high-speed information processing not only to tasks which require the high-speed information processing, but also to tasks which can be processed by low-speed information processing as well. Even if different communication ICs are provided for handling a plurality of communication protocols, if the communication ICs are separately controlled, it is impossible to fully simplify the entire wiring.
An object of the present invention therefore is to provide an integrated wiring system capable of flexibly coping with various communication systems.